Combustion piston

**s8nsmum** · 26th September 2006, 12:37

What are the rules concerning combustion inside a cylinder to power a weapon such as an axe or flipper. I am thinking building a system that will inject a fuel air mix into a custom pneumatic cylinder and then igniting it to provide a power stroke to fire a weapon. Would this be allowed and if so is there a limit on what I can use as the reactants? Would hydrogen peroxide or nitrogen dioxide be allowed?

**cavecrusher** · 26th September 2006, 12:55

i know mario had some fun ideas with using hydrogen peroxide in a combat robot

**leorcc** · 26th September 2006, 13:10

That all depends on the definition of fun. Id say this fals under de the IC engine rule, so it would mean only a limited supply of feul, and not every venue or event organizer will allow it to run.

**Kenny** · 26th September 2006, 15:49

I thought about this when building my ram but i then thought what if some reason the piston didnt move, it would be a bomb wouldnt it??

**jamesb** · 26th September 2006, 16:06

plus the air/fuel mix in a combustion engine is compressed before ignition, usually to 10 or 12 bar, so you will need a motor or co2 to force the ram down to get the compression needed for an efficient burn/expansion. Just injecting and burning will work, but you wont get ic engine sorts of force from it without precompressing the mix.

not saying it wont work, but it is not as easy as it sounds.

**s8nsmum** · 26th September 2006, 16:08

The only problem I can see is that there might be occasions where the pressure in the cylinder is very high. As there are no rules saying what the maximum pressure inside an IC engine is it wouldnt be breaking any particular rule but instead may be banned by the event organiser simply for being different or unproven. Anyone from XFM or Roaming robots want to give an opinion on this?

**killercarrot** · 26th September 2006, 16:17

I seem to remember an entry in RW2 or 3 that ran a spike powered in this fashion, they were using something like an agricultural gas gun (crow scarer) to feed gas into an ignition chamber and then fire the spike..